We know Asuna is going to go that far. She will;
I'm not sure there's a point after this that she can 'come back' from.
I suspect Administrator will be Kirito's final boss, at least in terms of FoG. This mirrors her status in Alicization, but I suspect we're in a weird post Alicization world, see below.
What exactly is Administrators deal, is yet to be revealed. In the show, she was just a fluctlight conciousness that was trying to escape to the real world. And we know Fujino hasn't exactly handled the canon of SAO too accurately. I think at this point in the story we're supposed to think Alicization has yet to happen (given the status of Asuna and Kyoko's relationship), but eh, the lore is a little all over the place, especially with Alicization. For example, Alice just showing up one day as a cop. And it's generally just all over the place with the characters, like with Kirito not knowing who Leafa is or recognising Asada.
What we know;
We don't see Admi in FoG, but that's the only place she should be as a digital conciousness.
We do see and speak to Admi in Kirito's dreams. Which means she's in his head, or;
We see the effects of Admi's power in the real world, through Inoda. Either that or those moments are a massive and intentionally misleading coincidence.
The logical explanation that is consistant with the facts is that what Kirito and Asuna think is the real world,
is not. It's another virtual game that they cannot escape, actually set in an alternate world post-Alicization. We can only really assume Admi's motivations to be something like she is keeping them trapped to try and break them up, or because she thinks it's fun to watch Kirito get tortured by the ruiniation of his relationship. Admi has mentioned something about 'The Core' before, and that she thinks Kirito will be the one to reach it. But she also has mentioned that the corruption of his relationship produces a lot of energy, or something.
If Admi escaped Alicization, she'd have come out like Alice did; a fluctlight brain in a robot body. She wouldn't be anything like a god. But maybe she isn't a god and Inoda just got lucky when he called out to her. But we
know Admi is at the very least in Kirito's head, because she hangs out in his dreams, something she could not do if she was in the 'real world'.